1. Field of the Invention
The invention relates to a substrate and a method of fabricating a display apparatus, and more particularly relates to an active device array mother substrate and a method of fabricating a display panel.
2. Description of Related Art
With the increase in computing power and the rapid development of internet and multimedia technologies, sizes of video or image apparatuses are miniaturized gradually. In the development of displays, along with the progress in optoelectronic technology and semiconductor fabrication technology, liquid crystal displays (LCDs) with superior features such as high definition, great space utilization, low power consumption, and no radiation have slowly become the mainstream of the market.
LCDs characterized by high contrast ratio, no gray scale inversion, little color shift, high luminance, full color, high color saturation, high responsive speed, and wide viewing angles are required in the market. At this current stage, displays such as twisted nematic (TN) LCDs equipped with wide viewing films, in-plane switching (IPS) LCDs, fringe field switching LCDs, multi-domain vertical alignment (MVA) displays and so on have been developed to satisfy the requirement of wide viewing angle.
In a conventional MVA-LCD panel, an alignment structure is disposed so that the liquid crystal (LC) molecules in different areas tilt in different angles and achieve the wide viewing angle effect. Here, the alignment structure includes the alignment protrusions located on the electrode or the alignment slits of the electrode. However, the light leakage arisen from tilt disclination of the LC molecules surrounding the alignment protrusions and the alignment slits leads to a reduction in a display contrast ratio of the LCD. To prevent light leakage, a light shielding layer corresponding to the alignment protrusions or the alignment slits is additionally disposed. Nevertheless, an aperture ratio of the display is limited thereby. Hence, a polymer-stabilized alignment (PSA) aiming at forming multi-domain alignment has been proposed, so as to resolve the issue regarding the unfavorable contrast ratio of the MVA-LCD panel.
The polymer-stabilized alignment (PSA) method needs to dope reactive monomers into the LC layer and applies a curing predetermined voltage thereto. The LC layer is irradiated by a light under the curing predetermined voltage. The reactive monomers are then polymerized and cured to form a polymer layer simultaneously on the substrate at respective sides of the LC layer.
Traditionally, the curing predetermined voltage applied is transmitted to the pixel arrays via a curing line disposed outside of a display region of the active device array mother substrate. Moreover, in conventional curing lines, the curing lines are fabricated from a layer that is formed simultaneously with a gate of the active device. However, when carrying out the subsequent process of the active device array mother substrate (such as the doping process), this curing line is easily affected by the following doping process and peels off from the substrate, such that the curing predetermined voltage can not be transmitted to the pixel arrays in the display region. As a consequence, the LC layer on the entire substrate can not be cured and aligned successfully, thereby severely affecting the yield rate and the fabrication of PSA-LCDs. Hence, how to improve the design of PSA curing circuit becomes one of the issues to be overcome urgently in the fabrication of PSA-LCDs.